High
E9 224 on Worcester Bosch 30i Junior

Your boiler has shut down because it has detected internal temperatures that are too high, meaning it has effectively overheated to protect itself.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Max thermostat activated – flue gas thermostat overheat

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

E9 219View →E9 220View →A1View →

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